Shoes for diving flippers and moulding device suitable for producing them

ABSTRACT

The object of the present invention consists of shoes for diving flippers and the molding device suitable for producing them. More specifically, the object of the present invention consists of shoes of different sizes that can be obtained from a molding device equipped with a minimum number of interchangeable elements.

The object of the present invention consists of shoes or diving flippers and the molding device suitable for producing them.

More specifically, the object of the present invention consists of shoes of different sizes that can be obtained from a molding device equipped with a minimum number of interchangeable elements.

It is known that diving flippers are formed from a blade and a shoe (part housing the foot), open or closed at the back, the size of which varies according to the size of the foot onto which they must be fitted.

In other words, for flippers, just as for any other type of footwear, it is necessary to provide the quoted shoe in variable sizes.

A flipper can be produced in a single material or in many materials.

In the first case a single molded product allows the entire flipper (blade and shoe) to be made. In the second case, in a first molding the blade is made generally using a harder material, and in a second molding the shoe is made, inserting the blade in a second mold.

The material of the blade is generally more rigid than that of the shoe.

In both cases, for each size a special apparatus (mold) is always needed.

This means that to make, for example, four different sizes of the same flipper, at least four different apparatuses (molds) are needed.

It is worth highlighting that the coat of molds and their replacement inside the machine for molding is extremely high and takes up most of the production costs.

In the simplest embodiment of a mold for producing swimming flippers in which the shoe is made from a different material to that of the blade a first mold is foreseen to produce the blade and .a second mold is foreseen to produce the shoe, suitable for receiving the same blade formed from at least three elements: two female half-shells, suitable for reproducing the outer surface of the shoe, and at least one male shell, suitable for reproducing the inner surfaces of the shoe.

The present invention has as its object a molding apparatus that drastically reduces the number of elements of the mold necessary for making blades and shoes of different sizes, in such a way reducing both the cost of the components of the mold and the time necessary to replace them according to the desired shoe size.

The shoe obtained through such a device also forms the object of the present invention.

The molding apparatus according to the invention foresees, for molding different sized shoes, a pair of female shells that can be used to make the outer surface of the shoes of all sizes and at least one male element of the mold that forms the inner shape of the shoe and that is therefore different according to the size of the shoe. Therefore, in a mold that can be reduced to three component elements, two female and one male half-shells, only the latter must be replaced to form different sized shoes.

This is possible since, according to the invention, the different sized shoes have the same outer shape and a different inner shape. Moreover, according to the invention, since the smaller shoes would have a greater thickness compared to larger ones, the inner surface of the shoe is defined through a suitable aeries of projections And ribs that allow the thickness of the shoe to be kept substantially unchanged, ensuring the same degree of flexibility for all sizes of shoes.

The essential characteristics of the invention are summarized and schematized in the claims; the objects and advantages of the invention are also illustrated in the following description relative to preferred embodiments.

FIG. 1 shows a longitudinal and vertical section view of the two female half-shells suitable for making the outer surface of different sized shoes.

FIG. 2 is a section view according to the section plane II-II of FIG. 1, which is vertical and transverse with respect to the shoe to be made.

FIG. 3 is a section view analogous to FIG. 1 in which, as well as the two female half-shells of the mold, the male half-shell intended for forming larger shoes can also be seen; between the quoted two female half-shells and the male half-shell the shoe formed inside such elements of the mold can also be seen in section.

FIG. 4 is a section view according to the plane IV-IV of the previous FIG. 3 but it is limited to just the shoe that in this case consists of the larger shoe amongst those that can be obtained with the molding apparatus according to the invention.

FIG. 5 is analogous to FIG. 3 and differs from it due is to the presence of a male member suitable for making a smaller shoe with respect to the one obtained by the assembly of component elements according to the quoted FIG. 3.

FIG. 6, analogous to FIG. 4, represents a cross section of the shoe illustrated in FIG. 5, according to the section plane VI-VI.

In FIG. 1 it is possible to see the two female half-shells 10 and 11, upper and lower, with respect to the shoe the outer surface of which they define through the opposite concave surfaces 12 and 13, situated between the points 14 and 16, and 15 and 17, respectively. The inner surface of the two half-shells defined between the points 16 and 18, and 17 and 19, respectively, is suitable for sealably receiving the rear part of the outer surface of a male member the front part of the outer surface of which is given the task of forming the inner surface of the shoe.

Therefore, it should be noted that, according to the invention, the inner surface of the two female half-shells reproduces the negative of the outer surface of the shoes of all the different sizes given that, according to the invention the shoes of all the different sizes have the same outer surface: as shall be seen the smaller shoes shall nevertheless be shorter and their outer surface will terminate at the rear before the outer surface of the larger shoes.

In FIG. 1 the rear profile of the larger shoe that can be obtained by the molding device according to the invention is indicated with reference numeral 20.

On the other hand, the rear profile of the smaller shoe that can be obtained with the same device is indicated with the broken line 21.

In FIG. 1, the inner surface of the upper half-shell 10 has, near to the point 16, a series of close grooves 22, 23, 24, 25, the purpose of which shall be indicated hereafter in the present description. The inner surface of the lower half-shell ii has, between the points 15 and 17, grooves 26, 27 and 28 that, in the same way as the groove 29 of the upper half-shell 10, have a different function: in a known way they are used to anchor the blade to the material of the shoe of the flipper that shall be molded in a subsequent step.

In FIG. 2, the height and width of the outer surface of the shoes of all sizes at the same cross section II-II having a constant distance from the point of the shoe are represented with H and K,

The height A represents the maximum length of the sole of the various shoe sizes that can be obtained from the device according to the invention whereas B and C respectively represent the greater lengths of the largest shoe and of the smallest shoe.

The ribs 22 and 25, as shall be seen, are used to create a stiffening edge at the rear lip of the upper of the shoe.

In FIG. 3 the male member 30 intended for molding the largest shoe can be seen, in combination with the two half-shells 10 and 11 which, on the other hand, are used for forming shoes of all sizes.

For this purpose the male member 30, with its rear outer profile, perfectly marries the inner surface of the two half-shells 10 and 11, between the points 16 and 18, and 17 and 19, respectively,

Between the points 14 and 16, and 15 and 17, respectively, the outer profile of the male member 30 moves away from the inner profile of the two half-shells, making an opening inside which the shoe 31 is formed. The cross section of the largest shoe is illustrated in FIG. 4.

Its outer surface coincides with the inner surface of the two half-shells 10 and 11 whereas the inner surface is defined by the outer surface of the male member 30.

It should be noted that the outer surface of the male member 30 is equipped with suitable grooves suitable for creating corresponding ribs 32 inside the shoe.

The purpose of such ribs is that of providing a comfortable contact between the surface of the foot and the inner surface of the shoe despite the inevitable size differences of different feet that take the same shoe-size.

These ribs take up a greater importance in smaller shoes. In the larger shoe 31, at the section II-II, coinciding with the section TV-IV, the inner width of the shoe is defined by the height D.

As stated above, FIGS. 5 and 6 refer to the device according to the invention equipped with the male member 130 suitable for making, in combination with the half-shells 10 and 11, the smaller shoe 131.

The outer surface of this shoe shall be equal to the outer surface of the larger shoe: its length C shall be shorter than the length B of the larger shoe. For this purpose the male member 130 shall have a perfect seal with the inner surface of the two half-shells 10 and 11 no longer from points 16 and 18, and 17 and 19 (FIG. 3), respectively, but from point 116, at the bottom of the groove 26 and the point 19.

The shoe 131 is therefore shorter than the shoe 31 but with the same outer surface.

The size of its inner surface, at the cross section illustrated in FIG. 6, are represented by the height DI that is lower than the height D relative to the larger shoe.

This decrease in height DI could also be obtained by simply increasing the thickness of the smaller shoe. Within certain limits, this solution could be accepted.

The present invention suggests a solution that is particularly easy to apply and that makes the shoe more comfortable, maintaining the flexibility of the larger shoe: instead of a simple increase in thickness of the shoe, there is an increase in the projection of the ribs 132 that allow, with the same thickness of the upper, a reduction in the transverse size of the smaller shoe. 

1. Shoe for diving flipper that can be made in different sizes, characterized in that the outer surfaces of the shoes of different sizes are all the same and the difference between the different sizes is limited to the length of the shoe and the shape of the inner surface of the shoe.
 2. Shoe for diving flipper, according to claim 1, characterized in that, alternatively and/or in combination, the smaller inner size of smaller sized shoes are obtained through an increase in its thicknesses and/or through ribs projecting from the inner surface of the shoe.
 3. Molding device for shoes for diving flippers, of the type that foresees at least two female and at least one male shells, suitable for defining the outer and inner surfaces, respectively, of different sized shoes for diving flippers, characterized in that it foresees a single series of female shells, for making the outer surface of different sized shoes, and different sized male members, preferably of decreasing size, for defining the inner surface of the shoe.
 4. Molding device for shoes for diving flippers, according to claim 3, characterized in that the male members intended for forming shoes of progressively smaller sizes are equipped with ribs of a size that increases as the size of the shoe to be molded decreases.
 5. (canceled) 